Urolithin A is a metabolite produced by some gut microbes from ellagitannin-containing foods. It has been studied as a mitochondrial and muscle-aging intervention. A randomized, double-blind trial studied four months of supplementation in older adults and measured walking performance, muscle endurance and mitochondrial-related outcomes.[1.1]
One selected study: A blinded, randomized trial tested urolithin A against placebo for walking ability, muscle endurance and cellular energy production. 66 adults aged 65 to 90 took part in a 4-month trial. In this randomized study of adults aged 65 to 90 years, participants received 1000 mg urolithin A orally each day or placebo for 4 months. This was the assigned study intervention; the abstract does not describe a starting-dose adjustment or any individualized regimen. Muscle endurance measures improved, but walking distance and the primary cellular-energy measure did not improve significantly versus placebo. This was a small study, predominantly in women, and all participants were White. The authors called for further confirmation.[2.1]
Studied methods, not dosing advice. Selected evidence, not a complete literature review or formal quality appraisal. Read the study summary
Source scope is listed with each reference. Prepared by PED Evidence with AI assistance. Independent clinician review has not been completed. Review standards
Evidence summarized on PED Evidence
7 completed summaries
5 human-study reports
4 randomized-trial candidates
0 safety-topic reports
These counts describe completed summaries on this site, not the size of the full literature. Publications can share participants; design labels are discovery metadata, not appraisals.
A randomized trial in older adults found improvements in muscle-endurance measures; between-group differences in the primary walking-distance and ATP-production endpoints were not significant.
What might this mean? · interpretation
Some functional signals are encouraging, with mixed results across endpoints.
What might this mean, and what would change the interpretation?
A selective positive endpoint cannot stand in for success across all outcomes or populations.
What would clarify this: Independent replication with prespecified functional endpoints.
More about Urolithin A: identity, safety & reference details
Small moleculeMitochondria
Primary research area
Emerging research
Regulatory status
Research status varies
Evidence level
Evidence level not yet characterized
Primary mechanism
Mechanism not yet characterized
Reference profile available · Coverage varies by section
What has been observed?
Selected source-linked reading notes, not the complete literature or a pooled conclusion.
Human · Reading scope not recorded
Do mitochondrial effects translate into human performance?
A randomized trial in older adults found improvements in muscle-endurance measures; between-group differences in the primary walking-distance and ATP-production endpoints were not significant.
Limits: A selective positive endpoint cannot stand in for success across all outcomes or populations.
A randomized, double-blind trial studied four months of supplementation in older adults and measured walking performance, muscle endurance and mitochondrial-related outcomes. [1]
Known half-life
No source-verified value in this profile yet. A treatment schedule or duration of an effect is not a drug half-life.
Half-life describes how quickly the measured drug concentration falls by half. It does not set a dosing interval.
Evidence & important limits
In the cited trial, the primary walking and maximal ATP-production outcomes did not differ significantly from placebo, while a secondary muscle-endurance measure improved at two months. The sample was predominantly female and White, and the authors reported commercial conflicts. [1]
Safety & evidence boundaries
Source-specific information, not a personal safety clearance or monitoring plan.
In the cited trial, the primary walking and maximal ATP-production outcomes did not differ significantly from placebo, while a secondary muscle-endurance measure improved at two months. The sample was predominantly female and White, and the authors reported commercial conflicts.
Interactions, rare harms, long-term effects and reversibility require separate evidence. Do not infer they are absent when the sources here do not address them.
Identity, names & formulations
Canonical compound: Urolithin A · urolithina
No additional aliases recorded.
Names share a parent research page. Different esters, salts, routes and brands are not assumed to have the same half-life, indication or exposure.
Combination evidence stays attached to the studied combination. It is not automatically assigned to each ingredient.
Understand the evidence types
Read the model and design first, then the population, outcome and limitations. These categories describe evidence, not a best-compound ranking.
Randomized human trials
Compare assigned interventions. Randomization does not by itself establish low bias or relevance to every population.
Controlled human studies
Use a comparison group; allocation and confounding still matter.
Prospective human research
Follows participants forward. It may be observational or interventional, so this is not a separate quality grade.
Observational human research
Describes associations. Confounding can explain differences.
Case reports and series
Useful for unusual events and safety signals, not reliable rates or effect sizes.
Animal research
Can test biology and function in a living model. Human exposure, benefit and safety remain separate questions.
Cell and tissue research
Tests responses in a preparation, including human-derived cells. It is not a human participant trial.
Mechanistic and computational evidence
Helps explain or predict a pathway; predictions need experimental and clinical testing.
Anecdotal reports
Self-reported experiences can generate questions. Product identity, selection bias and other interventions may be uncontrolled.
Systematic reviews synthesize studies and depend on their quality. Preprint status and abstract versus full-paper reading are separate labels. Citation popularity measures attention, not reliability. A study summary is not a formal quality appraisal.
Reference facts checked 2026-09-16. Source scope is listed above; this is not a formal quality appraisal. See each label for full prescribing information.